1. Technical Field
The present invention relates to a vehicle submergence detection apparatus for detecting submergence of a vehicle.
2. Related Art
A power window mechanism for opening/closing a pane of window glass by using a motor, or the like, has been generally set up in a vehicle such as a car in recent years. When a vehicle has such a power window mechanism, providing various submergence countermeasures to submergence in a sea, a lake, or the like, due to an unforeseen accident., or the like, has been discussed. A submergence countermeasure enables a crew member to escape out of the vehicle easily when the vehicle has been submerged, by opening a pane of window glass automatically, or securely opening the pane of window glass by a manual operation.
Such a submergence countermeasure uses a structure which has a submergence detection means for detecting a submergence state, a control circuit for controlling a movement, and a drive circuit for supplying driving electric power to a motor, or the like, to drive a pane of window glass to open/close the window. The structure enables the pane of window glass to compulsorily open or to securely open by operating an emergency backup circuit when submergence is detected.
In the above-mentioned submergence countermeasure, no technique for detecting submergence has ever been established sufficiently. In the background art, a special sensor unit having a light transmitter and a light receiver for detecting water invasion optically is used for detecting submergence. However, when using such a special sensor unit, there was a problem that the cost of the submergence countermeasure substantially increased, or that a large space was required for arranging the special sensor unit.